A household water softener system typically includes a resin tank through which hard water passes to exchange its "hard" ions of calcium and magnesium for "soft" sodium ions or other regenerant ions. Regeneration of the resin bed is required periodically to replenish the supply of "soft" ions and to remove the accumulation of "hard" ions from the bed. The regeneration is effected by flushing a brine solution through the resin tank. A water softener of this type is more fully described in U.S. Pat. No. 3,891,552, issued June 24, 1975 to William C. Prior and James W. Kewley, entitled CONTROL VALVE FOR WATER SOFTENERS, the disclosure of which is incorporated herein by reference.
Modern water softeners of the type disclosed in U.S. Pat. No. 3,891,552 typically employ a brine tank which includes a reservoir and a supply of salt disposed at a level above the bottom of the reservoir. A tube connected to a source of water provides a path for supplying water to the reservoir. Upon the attainment of a predetermined level in the reservoir, the water begins dissolving some of the salt supply and creates a source of brine for regeneration of the resin bed. When regeneration is required, the brine is aspirated through the same tube that supplied water to the reservoir. The amount of water introduced to the brine reservoir after a regeneration cycle and the amount of brine aspirated from the reservoir during a regeneration cycle is controlled by a brine valve mechanism.
Many prior art brine valves utilize float arrangements to directly control the level of brine in the brine tank as well as the quantity of brine solution discharged from the brine tank during a regneration cycle. The floats in these prior brine valves are usually exposed to the brine solution. An example of such a brine valve is illustrated in Pat. No. 4,336,134 which is owned by the assignee of the present application. The trend today in water softening equipment is to minimize the quantity of salt and hence brine solution that is used during regeneration and as a consequence, and it therefore is desireable to reduce the volume of brine solution stored in the brine tank. In order for the system to function properly, the volume of fresh water added to the brine tank as well as the quantity of brine solution withdrawn from the tank during regeneration must be precisely controlled. Although the brine valve illustrated in U.S. Pat. No. 4,336,135 operates satisfactorily and has been commercially successful, it has been found that under some conditions, the volume of water added to the reservoir after regeneration varies and as a result the brine solution quantity also varies. These types of brine valves are also sensitive to orientation and if the brine tank is not absolutely level, variations in liquid level will occur that will vary the amount of salt consumed for a given regeneration cycle.